The area of the wing that ailerons occupied on WWI aircraft is comparitively large, especially considering that they were often found on each wing of a biplane or triplane design.

Here's an excerpt from the book Fundamentals Of Fighter Design by Ray Whitford, that helps illustrates this issue:

The Camel was unstable in pitch and considerably unstable in yaw, with very sensitive elevators and rudder. When it was designed in 1916, ailerons were in their infancy, and the prevailing philosophy was if a faster roll is needed, make the ailerons bigger. The Camel had four big ailerons, requiring a large force to move them. When moved, the wing section was so degraded that the roll response was much less than, say, a Tiger Moth's. Adverse yaw arising from the aileron drag was the primary effect, aileron roll was secondary. Modem pilots who have flown Camel replicas have commented that if it was the best World War One fighter, 'God help the worst'. However, its stalls were gentle and predictable, spins quite controllable in skilled hands with low stick force/g. The Fokker Triplane, on the other hand, had very poor visibility from the cockpit and a small rudder that was very effective when its rotary engine's power was applied. The tail skid was not connected to the rudder which inevitably meant overcontrol with tail wagging on the ground. Like the Camel, the controls lacked harmony with a light and twitchy rudder and very heavy ailerons.

Of course WWI ailerons were not hydraulically actuated, or power-boosted, nor as in modern fighters electrically controlled thru fly-by-wire operation..............the result of the bigger is better philosphy; very heavy ailerons, oh and two-handed grips on joysticks!

Ironhand, did you get those two books I recommended, they would go a long way in helping you understand the characteristics of flying WWI aeroplanes...........by all means feel free to do the research yourself!

Hey Fly!!

I know the ailerons were not operated by hydraulic or anything else but muscle power
I was refering to the Zero

Of course many WW2 planes were also muscle power as well.

The only books I got so far are Richthofen, Beyond the Legend, and DR1 Aces of WW1.

Ahh, the things MvR had to say about rotary engines.....

Control harmonization between aileron and rudder?

Rudder -- legs, feet.
Stick -- arms, hands.

I'd be more concerned with aileron/elevator control force balance.

There was a saying some had about the Camel: If you can fly a Sopwith Camel, you can fly anything!

It is also one of the two WWI planes I know of with more training than combat losses, the other being the SPAD, IIRC due to the vicious roll tendencies and crosswinds.

I would expect those planes to be extremely responsive to stick movement just due to light weight at least in relation to WWII birds. In comparison to each other yeah there's differences. By responsiveness I mean how fast the plane begins to tilt or rock not roll, pitch or yaw rate itself.

No hydraulics in the Zero! Hydraulics are great for high speed, high forces and just large planes but they are slower changing than straight mechanicals.


Neal

Shall I quote the details about the Fokker Dr.I's aileron stiffness, even though these were horned-balanced?

Flight modeling should be a total package, and the human component in the equation should be modeled too.........this is especially important for WWI.

This has been the thrust of my argument, and hopefully in the future, attempts will be made to finally fully integrate the experience of piloting a plane into our flight simulations too!

It's about quality and immersion!

My recent reading told me that the ailerons on the Tripe were over balanced. Not a good thing.

I think I'm missing something here. The stick was purposely made stiff to move to the sides, right? Even just sitting on the ground? So in flight how did that truely affect things? Like you pull a small amount of stick and those short wings roll quick or not? Because the DrI wings were made short for just such reasons and the controls may have been made stiff to have them pull as a plane with longer and fewer wings would such as an Alb DIII which so many pilots were used to. When/if the plane will twitch to the smallest input then mechanically stiffened controls would be a bright idea just as good return springs on a PC joystick are. It would also help the plane in turbulent air.

Taking individual aspects of a system apart and abstracting on them is not good, what kind of roll *did* the DrI get for so many pounds of side stick and not how many *should* it? At least I hope this isn't what's being done.


Neal

In flight the faster the airflow over the ailerons the more force you would need to move the controls. I think the tripes rolled slow because there was too much wing area, too little control area.

I don't understand all of it, but I know that metal covered ailerons are better than the fabric ones. I guess because the fabric would be distorted by the air flow, while the metal ones would not be.

As always, feel free to enlighten me.

The Spad was called the flying brick, but not because it flew like one. It glided like a brick. You lost engine power you dropped like a brick.

I'd guess this is something that has occurred to everyone who has seriously thought about flight-sims. The problem is it's difficult to implement. The ideal would be to have force feedback genuinely make the stick stiffer to move to the correct degree; which would require a) very strong motors in the FF stick & b) more precise control than I believe FF technology currently permits.

It would also be a disaster for online - people without FF would have a massive advantage as they could put the controls at full deflection with ease at all times.

The other option is the one I believe most sims go for. Simply take the range of movement the user's joystick can travel to be the range of movement the "average" person could actually have moved the stick given the speed/manouvre currently occurring, and make the position the user's joystick centres on when left alone the same position that the virtual stick would centre on when left alone.

After all, when actually flying you don't think of the stick in absolute terms - centred absolutely, at full deflection etc. You think of it in relative terms - centre is where you don't have to exert any pressure (which will vary depending on speed and trim), and you judge position relative to how far you are capable of moving it, not how far pneumatics would be able to move it.

I think suggesting your input should simply signal intent to your virtual self is a mistake; it cuts you off too much from the events, kind of makes you a ghost standing behind him whispering in his ear rather than actually being him.

Rob

Rob

Neal,

High stick forces are not something generally designed into an aircraft's handling characteristics, although I have heard of it being done in the 1920's to dampen the potential airframe loads exerted during high speed maneuvering on some US fighter designs. As Ironhand stated, heavy stick forces are largely a result of the force of air flowing over the control surface during flight, along with the component's weight, and any movement friction caused by the system's mechanicals itself. The variable in the equation is caused by the fact that the faster an aircraft flies, the greater the force needed to deflect the control surface against the force of flight (against the force of wind flow). Interestingly, but perfectly understandable is the fact that when a wing is stalled, and the airflow is disrupted over the ailerons for example, the corresponding control effort becomes lighter because the amount of airflow has been diminished due to the stall (in fact the stick can go "limp" or "dead").

Now, before I go further here, let me again recommend the book Three Wings For The Red Baron, by Leon Bennett, which I think should be on every WWI aviation fans' bookshelf, and from which the following excerpt is drawn:

1917's horned ailerons were the hydraulic servos of its time-a means of reducing pilot operating load in order to gain greater maneuverability. Struggling to find the strength necessary to move a control is obviously not the way to gain speedy actuation. Any reduction of control loads helps. WWI's aircraft, though blessed with relatively low air loads, required much pilot effort to accelerate the control surface itself, a matter of overcoming inertia and friction opposing the desired change of position. Wanted was some form of boost in a low tech form, suited for front line combat.

Now let's take that bookshelf again, and remove our written treasures from it so we can borrow a leaf and go for a ride in the family car. Let's stick that board out the car's window at 50, 60, 70 mph, and attempt to pivot it on its pitch axis...........quite a bit of force is needed to deflect it against the moving slipstream and to hold it steady (in fact it's probably already been torn from your hands and is tumbling behind the car..........let's move on shall we)! This same principle applies when flying a WWI aeroplane, and it's only through human strength and leverage that control inputs are accomplished during high speed maneuvers. As mentioned in the quoted passage above, horned ailerons were a means to balance the effort needed to deflect a control surface largely by "neutralizing" the airflow forces working against this movement, but if you want to understand this principle further you'll have to get Bennett's book, because it contains many gems to be enjoy besides that briefly listed above.

Lastly, harmonizing controls is a means of equalizing the pressure (movement if you like) needed to deflect a contol surface, whether it be for actuating the rudder, elevator, or aileron. The object is to produce control force requirements that do not largely differ from one control surface to another................disproportionate force requirments causes difficulties in coordinating multi-axis maneuvers, and the fact is that most WWI aircraft exhibited poorly harmonized controls, which is understandable because the control surfaces themselves varied in size and area to a great extent within each aeroplane's design.

Now, bundling all these variables into a useable simulation "interface" is what is behind my idea for creating a pilot "entity" through which these multi-conditional variables can be realized.

In the final analysis it must be stated that many WWI aircraft were not particularly easy nor enjoyable to fly...............in fact they were work to fly, and especially so up to the edge of their flight envelopes. This fact is what made the flying capabilites of a Voss, or a Jacobs something to behold, even to this day, and which caused Manfred Von Richthofen to recommend against stunting to the average fighter pilot under his tutelage.

It's time to strongly consider the pilot's capabilities, and how changing flight dynamics impacted a pilot's ability to control his aircraft in flight. This is why creating a pilot "interface" between our joysticks and our virtual aeroplane intrigues me so much, because it could be the means for introducing the human element into sim flying, something which at present we are unwilling or unable to experience to a great extent in currently available flight simulations.

Mahoney,

The idea is to have your pilot (interface) being your force feedback, as well as your wound feedback, as well as your inverted "hanging from the straps" unable to push the rudder pedals feedback.

I know of no sim that introduces flight forces that the pilot must overcome first to pilot his plane...........the result of over-control is usually speed bleed penalties or stalling.

Could you enlighten us as to which sim actually considers a varaible "range of motion" for aircraft control based on force input requirements versus pilot stength during different moments in time?

Is this a feature needed for modern-era sims?

Is it a feature incorporated in WW2 era sims?

Hey, I'm truly interested in knowing if this concept has been done before, because I'm unaware of that, so please let us know!

Well, the Il2 series allows you to adjust roll, pitch and yaw and stick deadband.

There are 10 bands to adjust for each one. You may want the stock setting for roll, which I think is 10, 20, 30, and so on. You may want to go 1, 5, 9, 13, etc. You may want to make them all 100.

Ironhand,

This is exactly against the spirit of what should be enabled in a WWI sim, in my opinion!

I'm of the thinking that there should be no way to adjust out the lack of control harmony that existed during this era of combat aircraft.

Remember, one of the advantages of having this pilot interface, is that we project out intention by our joystick movements, but the virtual pilot can only execute what could be done within the possibilities of the moment at hand! So although we deflect our Wizz-bang No.4 joysticks completely over to the left in a desktop roll, this doesn't mean our virtual pilots will be able to do this immediately in-game, because the interface will judge what is possible within sim itself.

So dial away with those joysticks, but just remember there's a virtual pilot in that flight seat that has to do the real heavy lifting!

You could even think of this as an anti-cheat mechanism, but why make this concept anymore confusing than it probably already is to some now anyway.

I don't think adjusting Stick sensitivity (calibrating) in IL2/FB or any other Sim for that matter should be a problem...
Aircraft still can only preforrn within its own FM.

You can have your non-adjustable interface when everyone has force feedback hardware that reacts the same. Until then you are looking at a near total mess. We would also all need sticks of real lengths to achieve historic control ability, not these under 1 foot wonders that are the size of FBW jet sticks. So dream on, such a sim would get such bad reviews by users that the company would have a poor name in the industry unless the software only sold with a hardware package, probably including the computer as well. Is the government in need of a WWI combat flight sim however real? Because that may be the only way to achieve a workable customer base that pays enough per copy.

Aileron deflection and boards out the car window... try hinging the board on a solid mount and deflecting it less than 20 degrees as an extreme maneuver you don't hold for long. What is the top speed for a DrI? How much envelope do any of those planes have? Do any get anywhere near mach speeds, into compression? There is no need to apply WWII control force arguments to WWI planes. They weren't easy is a given but I will take any anecdotes as being relative to the times and planes of the times until I see better. I have read more about cold temperature, winds and oxygen starvation above 12,000 feet (in fact those things many times) than G forces except in spins where they'd be noted as pinning a pilot to one side of the cockpit. I've seen zero from pilots about how hard it was to pull stick which even some of the same pilots later wrote of early 109 controls.

WWI fighters could pull a few G's but not for long without losing alt. They didn't have the power to sustain such. You turn, you lose E. Sustained turns in those planes were either small radius at slow speeds or large radius and low degrees per second. As Mahoney pointed out, leave the matter to stick wankers blowing energy and only realistic behaviour will get good performance, the worst cases won't even stay in the air let alone make any shots or --gasp-- be able to exploit holding on to unrealistic high G turns just because the controls are not 'as real'. If the external model is real enough then it will sort things out.

DrI. Short wingspan x 3 wings. Unlike Sop Tripe full wingspan x 3 wings. DrI. Short fuselage with smaller rudder, shorter lever arm and shorter throw with much less frame weight and much less side force against turning, a full sized rudder would overcontrol it quickly. Anthony Fokker knew what he was doing and was one very good designer. I'm not saying he did miracles but he pulled off some of the best designs of the war. The drI also had the Gottingen thick wings which were the only close thing of the times to later 'modern' wings when the NACA profiles are compared.

The answer about controls and flight characteristics is very simple. Some money and some time, go to Old Rhinebck or a similar place where they have and fly very close replicas and either ask the pilots or pay enough to train somebody already an aerobatics pilot and get the information from a horses mouth. The means exists to get good enough approximations to base extrapolations into what the replica pilots will never do, full strain ACM's.


Neal

LOL! I already have asked Neal, now it's time for you to do your homework.

I haven't seen you post anything in the way of Q&A between you and anyone who flies or flew any WWI replicas. How much pull sitting on the ground versus how much pull at full level speed? When does the stick force get too much to be able to make full deflection? Is there any need at all for anything like full deflection at high speed in those planes or would the resulting force tend to warp or break the wings?

If you're suggesting that I get out to Rhinebeck, the closest of those field I know of, and ask then sorry bud but I can't swing it, please don't get "smart" about it either. I suggested it would be something that a company making a WWI sim might want to do as the info might be a savings and a good advertising point.

BTW, there's a number of people who have gone and asked but didn't ask the right questions, didn't follow up well on the answers, and couldn't do either since they were just fielding quick informal Q&A back and forth and not sitting down for anything in depth. Did you see any of Chuick Holdens report from Rhinebeck?


Neal

Gotta a little story for you Neal:

FlyXwire: Excellent information baldeagle!

I have a few questions on your flying technique, and hope you can comment on the work of the rudder in inducing roll.

1) How much aileron was needed to prevent the Dr.I from attempting to roll into the direction of the flat turn?

2) With your flying experience in the Dr.I, and other WWI era aircraft, or the PT, how would you characterize the role of the rudder (as compared to modern civilian aircraft) to affect rolling?

3) Connected to question (2), would you characterize the triplanes ailerons as working more to "balance" turns (to limit rudder induced roll, and/or to prevent adverse yaw), or as the primary control surface for executing banks?

P.S. I was at Dayton too, and might have seen you up there!

baldeagle: FlyX, I just got back today from the Monocoupe fly-in at Creve Coeur Airport in St. Louis. Wish I'd thought to time the rate of turn of the Monocoupe to see how it compared. One of the biggest differences between flying modern aircraft and flying vintage aircraft is the importance of the proper use of the rudder in the older types. If you don't believe it ask "Heater" Heatly, the F-14 pilot who crashed the Triplane I used to fly at Rhinebeck. He discovered, too late, that rudder pedals were used for more than steering the machine around the carrier deck. He let the Dr.1 yaw so much, first one way, then the other, right after take-off, that it finally stalled and spun in. If he had not hit the telephone wires at the South end of the Aerodrome he would've been killed, as it was they broke his fall and he walked away from it. Nothing was left worth saving but the rudder, one side of the rudder fabric from it is on the wall of my old bedroom at my parent's house.

Good question about the flat turn, the Triplane does indeed want to bank into the turn, even though it doesn't have dihedral. You do have to hold opposite aileron to keep it from banking, which doesn't seem like something you'd do in combat. The ailerons are important in turning, more so than in an SE-5 or other aircraft with dihedral (Fokker D.VII), which tends to convert yaw into bank. If I remember right, the SPAD that is now flying at Rhinebeck would yaw sloppily without banking unless aileron was put in, again no dihedral.

Pretty much all of the WW1 aircraft have a lot of adverse yaw when you put in aileron, so the rudder is important to take care of this, most modern aircraft have friese type aileron hinges to do away with adverse yaw, a lot of them can be flown through turns with your feet on the floor. Not so the old stuff.

FlyXwire: I was wondering if you could comment a bit more on the crash of the Old Rhinebeck Dr.I?

At the time of Heater's stall, what was the pitch attitude of the triplane (if you can recollect)?

What was the role of drag and airspeed bleed in the resulting stall and spin, as compared to the AOA?

Thanks!

baldeagle: I wasn't there at the time, but my father was. He said that they first had Heatly fly a Cub and then a Great Lakes to prepare for the Triplane, in hindsight not enough transition. My dad said to him that there must be quite a difference between flying an F-14 and the old planes, and he said that Heatly replied, "Yeah, it's kind of boring."

I believe that the Triplane was within hearing distance, and thought, "What? We'll see about that..."

I think that the jet pilot equated simplicity with being easy, and thought that because the stuff he flew was so complicated that it must be much harder to fly. Not true when it comes to stick and rudder.

They said that as soon as he broke ground he started to yaw to the right, eventually heading almost 90 degrees to the runway, then yawed back to the left almost 180 degrees, all with the nose level, before the airplane finally stalled, and being in wildly uncoordinated flight, snapped into the beginnings of a spin, interrupted by the ground. He disappeared behind the small trees at the south end of the Aerodrome going straight down and crashed. Nobody wanted to go down there and see what was left, but of course they did, and "Heater" was pulling himself out of the wreckage. The left wings, I believe, had caught the telephone wires, turned the airplane sideways, and the right wings absorbed the impact, saving his life. He landed right on the road, last time I was there you could still see the splices in the telephone wires. "Heater" of course cried, "Wind shear!"

Stories are common in the vintage aircraft world of jet pilots taking the controls of old airplanes and being notoriously unaware of what the rudder pedals are for, since the jets apparently will fly fine with your feet on the floor, until you need to steer around on the ground. The Triplane is of course more critical than most in this regard because it will yaw so easily, with no fin, and that small but sensitive rudder.

They wanted somebody who could talk first hand about the differences between an F-14 and a Fokker Triplane for a PBS documentary called "Top Gun and Beyond", I've always said that they should have let me fly the F-14...

Great story isn't it!!!

Besides the insights the discussion illustrates on the issue of WWI pilot controlability, and how piloting the old warbirds differs substantially from modern military or civilian flying today, the story cautions to never disregard well-intentioned advice given by others, unless you know it to be expressly untrue, and then maybe take a second look just in case.........

Ok Neal, it's time for you to show us what you've got!

I've been asking questions for years about WWI aircraft flying, and have accumulated a few solo flight hours of my own under my belt, so unless you're awfully sure of what you're talkin' about, maybe it's time now for you to go back and do that homework..........again.

I am sure Aspect has done their research. They more than likely looked at pilot accounts. They looked at any available NACA charts.

But I would hope they spend more time and effort on making the aircraft as realistic as possible than on things like a virtual pilot. Or men pushing your aircraft out of the hangar.

I suspect it will have an updated RB type campaign. Two actually, as one will be the one in which you will be able to influence the war.

Heck, if it turns out that they made a RB campaign with far superior flight models and more aircraft choices and better missions, I would be happy.

But I suspect it will be better than that.

However, I don't want to have to go through flight school before I can play. Or have to ride a truck from the chalet to the airfield. Or yell at the mechanic "Switches on!!" and watch him pull down the prop.

Or see him slip and get beheaded by that prop.

You've got the ear of a source FX, so keep the info coming! How about something on overwhelming stick forces?

The rudder he says is a bit oversensitive? So, not too small then? Why I don't think it's as much of a problem as unbalanced pitch and roll is because those are worked with the same arm, a bit different with training your legs to do one thing and your arms another. Not saying it's easy mind you.

Apparently from some reading the Spitfires were much more sensitive on the pitch axis of the stick than on the roll. Some people want FB to be like that to the pounds of pull, but then they do not fly Spits in that sim but rather the opposition.

The Point there is the same as here. In the real plane, the pilot has a full length stick and complete feel of not only the stick but the movement of the plane. Without those an oversensitive control system becomes a liability without the compensating sensitivity and response of the real thing.

In a SIM you have to compensate for the places where REALITY is not covered, one being the hardware and another being the lack of motion feedback. And I don't need to do any freaking Homework on that, been and done. It only takes some sense and time to understand.

It would be great to have the adverse yaw where true, to need to hold the wings down on turns in one plane while fighting to get them banked in yet another. No sim has done that. Hell it would be great if just for once a multiwing combat flight sim used true multiwing FM's instead of tweaked monoplane modelling, one place that RB blew it.


Neal

Actually, Aspect has been aware of this idea since June, so it' up to them to implement it for KOE or not.

People have different desires, so their's always going to have to be accounting for personal taste, but one thing stays pretty much consistent.............almost anyone can recognize quality and immersion!

Sorry, but the more I drum this in, the more likely you guys will eventually "get it"!

In fact I see some positive movement already, but it's almost unbareable sloooooooooooow............LOL!